diff --git a/iiif_manifest.gemspec b/iiif_manifest.gemspec
index f08da87..e04bfa5 100644
--- a/iiif_manifest.gemspec
+++ b/iiif_manifest.gemspec
@@ -11,6 +11,7 @@ Gem::Specification.new do |spec|
   spec.summary       = 'Generate IIIF presentation manifests for Hydra::Works'
   spec.description   = 'IIIF http://iiif.io/ defines an API for presenting related images in a viewer. This transforms Hydra::Works objects into that format usable by players such as http://universalviewer.io/'
   spec.homepage      = 'https://github.com/samvera/iiif_manifest'
+  spec.metadata      = { "rubygems_mfa_required" => "true" }
 
   spec.files         = `git ls-files -z`.split("\x0").reject { |f| f.match(%r{^(test|spec|features)/}) }
   spec.bindir        = 'exe'